Current procedures for making dental models require certain process steps to be carried out after the final unhardened and moisture containing porous refractory model is made, and prior to its waxing-up. These required process steps normally consume several hours and frequently resulted, among others, in the following: (a) the porous model, which has now been subjected to the drying and hardening steps would be softer than desired, while the lacquer or beeswax coatings on the hardened model would be more porous than desired, (b) the lacquer or beeswax coatings would be thicker than desired, often necessitating extra grinding and/or polishing of the ultimately formed alloy prostheses, (c) these coatings would have a rougher surface than desired to thereby cause similarly rough surfaces to form on the tissue side, for example, of the ultimately formed framework or dental prostheses, thus requiring correction, (d) the presence of some water vapor in the porous model which may not have been adequately dried in the drying or burn-out operations often causes bubbles or other surface defects to be present in the alloy prostheses.
The present invention substantially eliminates the aforementioned deficiencies by providing a simple spraying of a cyanoacrylate solution onto surfaces of the unhardened porous refractory model. The spraying step consumes but a few seconds to perform and renders unnecessary the heretofore required steps of drying the final porous refactory model in an oven, allowing the dried model to cool to room temperature, hardening the dried and cooled model, and spraying the hardened model with, or dipping it in, a lacquer or beeswax solution in an attempt to provide a shiny nonporous surface thereon.